Surgical and dental chair



(No Modem 's sheets-sheet 2.v

. A. P. GOULD.

SURGICAL AND DENTAL CHAIR.

Patented June 23, 1896.

ments in surgical and dental chairs; and it Nrrnn- STATES v AARON P. GOULD,

SURGICAL AND rricn.:

or CANTON, OHIO.

DENTAL CHAIR.

SPECIFICATION forming part 0f Letters Patent N. 562,391, dated June 23, 1896. Application filed February 25, 1895.` Serial No. 589,561. (No model.)

T0 all whom t may concern: i

Be it known that I, AARONP. GOULD, a citizen of the United States, and a resident of Canton, county of Stark, State of Ohio, have invented a new and useful Improvement in Surgical and Dental Chairs, of which the following is a full, clear, and enact description, reference being had to the accompanying drawings, making part of this specification.

My invention relates to certain improveconsistsin providing means for raising and lowering the chair-body, and for supporting it in desired elevation.

IVith these ends in View my invention consists of certain features of construction and combination of parts, as will hereinafter be described and claimed.

Figure 1 of the accompanying drawings is a view in perspective illustrating my invention. Fig. 2 is a vertical section. Fig. 3 is horizontal section on liney fnl/ of Fig. 2. Fig. 3 is a detail perspective of a portion of the base and the linko. Fig. 4 is a vertical section on lines .e e', Fig. 3. Fig. 5 is a similar view on line Y Y, Fig. 4.. Fig. 6 is a view of the inner end of the lifting-lever from the inside, showing thepawl and trip. Fig. 7 is a side viewof the rack-wheel. Fig. 8 is a side view of the inner end of the lifting-lever from outside, showin the lever-liftin g spring. Fig.

9 is an elevation of the lowering mechanism from the front side. Fig. 10 is a longitudinal section of the air-cylinder.

its support. Fig. 12 is a section through the rack-wheel and a fragment Of the base, showing the lifting-pawl in engagement with the rack-teeth. Fig. 13 is a similar view showing the pawl out of engagement with the rackteeth.

A denotes the base, having upwardly-projected portions B, to which is pivot-ally se- Fig. 11 is a longitudinal section through the head-rest andA "adjustment about its pivotal connection with the arm D a rack cis provided, as shown in Fig. 2, secured to the arm D, and a springlpawl d* is pivoted to the support, as shown `at e, said pawl having pedals f projected therefrom, by which the operator may disengage the pawl from the' rack, the spring g serving to hold the pawl in engagement with 'the rack, thereby securing the parts in adjusted position.

To raise the chair-body E, a spur or rack wheel G is looselymounted on a non-rotative shaft h, secured in the base .A, said wheel having engagement with the rack H, the upper end of which has a pivotal engagement with the arm C, the lower end to pass down `into the base, as shown in Fig. 2.

The rack-wheel Gr has in its side a recess j, in which is loosely mounted on the sleeve `7.a, or if, preferred, on the shaft h, a clutchhead I, supporting a pawl Z, (see Figs. 6, 12, .and 13,) the outer end of which will engage the rack-teeth fm, provided on the inner surface of the wall of the recess j. 'Io the hub n of the clutch-head I is secured an actuating-lever J. When the outer end of the lever J is raised, the outer end of the pawl will be carried down to be in readiness to engage a toothm, near the bottom portion of the series. The reverse movement of the lever will bring the pawl into engagement with one 1 of the teeth and thereby rotatethe wheel G, 1 to raise the rack H, and the arm C, and the y parts connected thereto; and to impart a simultaneous upward movement to the arm D, and the chair-body supported thereon, a chain ofgear wheels 1 2.3 4 5 are loosely mounted on pins or studs secured in the `downwardly-projected side flanges of the r arin'C.l Wheel 1 isconnected to the top portion of the base by a link o, pivotally secured to the lugs p, as shown in Figs. 3 and 3, and wheel 5 is connected with the arm D by the link q, as shown in Fig. 2.

Vhen the arm C is folded down over the base, the lowest point of adjustment, the upper end of the link o will occupy the position indicated by the dotted lines; the arms having been lowered, will carry the center of the wheel 1 down below the end of the link. Having assumed that position now, as the lever .I is pressed down, the pawl Zwill en- IOO gage the rack-teeth m, by which the wheel G arm C, which movement will cause the wheels l 2 3 4 5 to rotate (the wheel l being held rotatively to the base by the link o) in the direction indicated by the arrows; wheel 5, having a link connection with the arm D, will raise the arm D up to the position shown in Figs. l and 2, or to any desired point of limit of movement. When the lever .l is released, the spring .e2 (shown in Fig. 8) will raise the outer end of the lever, by which movement the finger z3 will engage the top of the base to draw the pawl out of engagement with the rack-teeth fm.

To lower the arms C l) and chair-body E, a non-rotative shaft r is secured in the base, as shown in Fig. 3, on which is loosely mounted a worm-wheel K, having in its side a recess s, provided with rack-teeth t, as shown in Fig. 5. On the same shaft r is loosely mounted a pinion L, as shown in Fig. 3,having teeth to engage the teeth of wheel G. At the side of the pinion is provided a hub eX- tension u, to which is pivotally secured a series of gravity-pawls w, one or more of which may at all times be in engagement with the rack-teeth t. A worm-shaft, as M, is journaled in the base A, as shown in Fig. 5, to engage the worm-wheel K. At the inner end of the shaft is provided balls a' to prevent friction caused by the thrust of the'shaft, and at the outer end of the shaft is mounted a iiy-wheel N, having on its inner side or face a ratchet a2.

As a break or resistance to a too rapid descent of the chair-body, an oscillating cylinder, as O, is provided, having trunnions at the sides thereof, by which it is supported in the lugs d3 provided therefor. In the cylinder O is provided a piston-head a4, having a small aperture a5 provided therein, as shown in Fig. lO. On the outer face of the flywheel N is provided a cross-bar a6, having a series of apertures a7 provided therein, adapted to receive a wrist-pin as, to which the piston-rod a9 is connected.

To start the wheel N to rotate and to stop rotation, a pedal-lever P is loosely mounted on the worm-shaft M, between the ratchet a2 and the base A. To the lever P is pivotally secured the upper end portion of a standard h', the lower end of which is supported in an aperture b2, in the base. About the lower end of the standard b is provided a coilspring b3, the lower end resting on the base, and the upper end to rest under an outwardlyprojected arm b4, on which is provided a shoe b5, to engage the wheel N. At the upper end portion of the standard 73' is pivotally secured a gravity-pawl h6, having a nose 727, adapted to fall into engagement with the teeth of ratchet a2.

To operate the lowering devices, the lever P is pressed down quickly; the nose 717 of the pawl b, engaging the rack a2, will give the ily-wheel N a start, which will be continued by the pressure of rack Il on. wheel G, and by wheel G on pinion L, and, through the clutch mechanism, the worm-wheel will be rotated against the worm on shaft M, which will be rapidly rotated to lower the rack II, and the parts supported thereon, the movement of the wheels l 2 3 4 5 to be reverse to that indicated by the arrows, hereinbefore mentioned.

Vhen the lever or pedal P is pressed down, as before stated, the pawl 796 will be carried below au d out of the reach of the teeth of the ratchet a2. To arrest the descent of chairbody, the pedal P will be released, the energy of spring b3 will raise the pedal and standard until the brake b5 engages and stops the rotation of the fly-wheel.

As a resistance to a too rapid descent of the chair-body, the hereinbefore-described cylinder and piston connection with the iiywheel N are provided. In operation, as the wheel N is rotated, the piston-head a4 is rapidly moved back and forth in the cylinder, which movement is resisted by the air in the cylinder, which, to allow the movement of the piston, as before stated, must pass through the aperture a5 provided in the head, as sh own in Fig. l0, which may be made or sized to determine the speed of the descent of the chairbody.

Q denotes a head-rest support, adapted to slide vertically in a back-support R, that may be secured in vertical adjustment bythe setscrew h. At the upper end of the support Q is provided a forwardly-projected arm h2, having hinged to its forward end an overlapping rearwardly-projected arm h3, having vertically therethrough an elongated aperture or slot h4. To secure the arm 71.3 in desired adj ustment about its hinged connection with the arm 7a2, a longitudinal aperture h5 is provided in the arm h2, in which is placed a plug 72,6 and a set-screw 7N. By the latter the plug 71, may be driven against the hinge portion of .the arm h3, whereby it is held in desired adjustment about the hinge-pin hs. On the upper face of the arm hsis placed a sliding block hg, having at its front end a spherical socket 7d, and at its middle portion a rubber spring 7a2, and at its rear end an aperture 7613, to receive to receive the tightening-bolt 7a4. Over the block 7t9 is placed a cap-piece 705, adapted to cover the block 7L, the lower edges not, however, to rest on the face of the arm h3. At the under side of the front portion of the cap is provided a spherical socket 7c, and at rear end portion an aperture ks, to receive the bolt 7a4. The cushion-support 7916 is provided with a ball 707, adapted to the spherical socket form ed in the block h and cap 765. A handlenut 7co is turned on the bolt 7a4, to clamp the cap on the ball and the cap and block on the arm h3.

In operation the cushion may be moved forward by slacking the handle-nut 769 and moving the bolt 704 forward in the slot 7b4', or the parts may be turned out laterally to the arm IOO IIO

71.3, or rotated about the bolt 7a4; and when desired the screw 71.5 may be slacked and the arm 7b3 and cushion turned down in front of the back cushion R and extended down in front to reach the head of a child. When the handle-nut 7.99 is slacked, the rubber spring 7a2 will raise the cap 705 and release the ball 707, so that it may be moved or rotated in the spherical socket and secured in desired adj ustment by the handle-nut 7c.

Having thus fully described the nature and object of my invention, what I claim isl. The combination with the base and seat of a chair, an arm C pivoted to the base, and an arm D pivoted to the seat, said arms being pivoted together of a lifting mechanism, comprising a rack and rackswheel, the latter having peripheral teeth, and internal teeth formed in its side, a foot-lever provided with a pawl to engage the internal teeth, a train of gearswheels supported on the arm, C, one of said wheels having a link connection with the base, and another a link connection with 4 the arm, D,whereby the movement of the arm, O, may be transmitted to the arm, D, substantially as set forth.

2. The combination in a surgical and dental chair, with the base and seat of the same of a lowering mechanism, comprising a rack, a rack-wheel, a worm-wheelV and worm, the pinion, L, and clutch devices between said pinion and the worm-wheel a Wheel rotated by said Worm, and an oscillating cylinder, a piston-head in said cylinder, a piston-rod connected with said wheel, whereby the pistonhead is moved in the cylinder against the air therein, to resist the movement of the wheel and worm to regulate the descent of the chairbody, substantially as set forth.

The combination in a surgical and dental chair, with the base and seat of the same of a mechanism to start and stop the movement of the lowering mechanism, comprising a fly-wheel that is rotated by the descent of the chair-body, a rack-wheel secured to said flywheel, a pawl to engage the teeth of the rack-wheel, a foot-lever to operate said pawl, and a brake to engage the fly-wheel, substantially as set forth.

Ll. The combination with a head-rest support R, of the vertically-adjustable stem, a means for securing said stem in desired vertical adjustment, said stem having a forwardly-projected arm, to which is pivotally secured a rearwardly-projected plate or arm, having a longitudinal aperture therein, and adapted to be rotated about its pivotal connection with the before-mentioned arm, ahandie-screw, whereby said arm or plate is secured in desired adjustment about its pivotal connection with the first-mentioned arm, a block to slide on the hinged arm or plate, having at its front end a circular recess, a cap to pass over said block, having a circular aperture to register with the circular aperture in the block, a cushion-frame having` a spherical or ball portion adapted to the spherical socket, formed in the block, and the cap, and means whereby the block and cap may be drawn down upon the plate, and the ball, to secure the parts in desired adjustment as set forth.

In testimony whereof I have hereunto set my hand this 15th day of February, A. D. 1895.

AARON P. GOULD.

Witnesses:

W. K. MILLER, OHAs. R. MILLER. 

